<div dir="ltr"><div class="gmail_default" style="font-size:small;color:rgb(51,51,153)"><ol><li>'unavailable' means the server will automatically and temporarily be removed from the pool of servers managed by the upstream (same effect as manually parametering it as <span style="font-family:monospace,monospace">down</span>)</li><li>the <span style="font-family:monospace,monospace">fail_timeout</span> parameter documentation of the very section you provided a link to is pretty clear: this value both configure the duration during which the parametered amount of failure must be recorded and the time during which the server will subsequently be unavailable<br clear="all"></li></ol></div><div class="gmail_extra"><div><div class="gmail_signature" data-smartmail="gmail_signature"><font size="1"><span style="color:rgb(102,102,102)">---<br></span><b><span style="color:rgb(102,102,102)">B. R.</span></b><span style="color:rgb(102,102,102)"></span></font></div></div>